What if testing your hair could reveal the truth about your health?

Hair-strand testing is the latest at-home health test, but does it live up to the hype?

When it comes to wellness, we’ve gone from asking, “Am I healthy?” to “How healthy am I?”—a shift in attitude undoubtedly spurred on by the slew of medical tests that one no longer needs a doctor’s appointment to carry out. Today, everything from our DNA to our gut microbiome can be swabbed from home and sent off for detailed analysis.

The latest DIY test is hair-strand testing. Once the preserve of drug authorities (it’s the only test that can detect illegal drug use once a substance has left the rest of the body), health companies have now wised up to hair’s potential for analysing everything from beneficial minerals to harmful toxins. But before you reach for the scissors, what does a hair test actually involve? And among the myriad health checks available, how do you know if it’s the right one for you?

The process

“The theory behind hair testing is that once toxins (drugs, alcohol or heavy metals) are ingested into the body, they go into the bloodstream and end up in hair follicles where they accumulate as a deposit (which can initiate unexpected hair loss in many),” explains nutritionist Kamilla Schaffner. “Hair is a waste product,” adds Dr Sharma, an integrated physician and the author of Live Longer, Live Younger, “in so much as it carries pollutants and toxins out of the body.”

This is why it’s the newest growth (ie right next to the roots) that hair-strand tests require, since this is the part that will reflect your most recent health status. At-home test kits require you to cut off about six centimetre-wide chunks of hair at the root (from all over the back of the head, so you won’t be left with a bald patch), before chopping off and discarding the majority of the length, leaving you with a heaped teaspoon of “new” hair to send off in the envelope provided.

At the lab, the hair is screened for a full range of minerals (including calcium, magnesium, zinc and sodium), toxic elements such as mercury, chromium, arsenic and lead, and additional elements such as tin, lithium and nickel, which in small amounts are thought to be beneficial to health. About two weeks later, you’re sent a full report of your various readings.

The pros

It’s important to note that hair-strand testing doesn’t claim to be a diagnostic test, but devotees say it can be a useful additional tool to detect key mineral and toxicity levels (often before any physical symptoms present themselves). The fact that the test measures elements that have a clear correlation to our health—studies into the impact of toxins have found links to everything from cancers to osteoarthritis, while beneficial elements like lithium are thought to lessen suicidal thoughts and promote brain health.

“Hair-strand testing can be a good method of seeing the extent of drug and alcohol use and their impact on a person’s health,” explains Schaffner. “Through them one can determine the levels of their toxicity. Frequently, people are very surprised to see relatively high levels of alcohol and drugs being detected, as hair-strand testing is unique in its ability to trace a person’s toxicity back months rather than days.”

“Research from The Journal of Clinical Endocrinology & Metabolism suggests that measuring cortisol in the hair, or by-products of this stress-coping hormone, can give an indication of stress levels,” adds Dr Sharma. “Blood, urine or saliva fluctuate day to day, whereas hair may give a longer evaluation.”

It is therefore hair’s ability to tell the whole truth (not just a reading for any given day) that has caught people’s attention. “It’s a good retrospective method of understanding how long a person has been suffering with their condition,” says Schaffner. “It’s not uncommon to detect high levels of heavy metals such as cadmium and lead in cigarette smokers, or high levels of mercury in people consuming fish from contaminated waters.”

The cons

While its ability to give a long-term picture of our health is hair-strand testing’s strength, ironically, that also appears to be its weakness. “Results are indicative of what was in the body but not necessarily what is still in the body,” explains Dr Sharma. “Also, only a few studies do a direct comparison of hair-analysis results to other established tests (blood, urine, saliva or stool), so accuracy remains questionable.”

The fact that only certain aspects of a person’s health can be measured (hair can’t give an indication of hormone levels or thyroid function, for example), means that other tests are still considered more reliable. “There are not enough aspects covered by hair analysis to offer a broad health screening, so, personally, I would not use hair when other tests are available,” says Dr Sharma. Schaffner agrees. “I only suggest hair-strand testing if exposure to toxic substances or heavy metals is known and a patient wants to ascertain the severity and duration of their toxicity levels. Otherwise, it can be an unnecessary tool, particularly in determining one’s biochemistry—blood tests are more accurate and have the added benefit of also indicating your level of hair health by looking for iron, ferritin and thyroid function.”

The verdict

While hair-strand tests offer another insight into the state of our health, they aren’t meant to replace traditional diagnostic methods such as blood and saliva tests. That being said, there is evidence that hair can and does indicate key health markers. “Certain minerals and toxic metals (for example mercury) have acceptable levels of evidence regarding the relationship to the amount found in the hair,” says Dr Sharma.

Whether this is enough to make at-home hair-strand testing as ubiquitous as DNA testing, only time will tell.